of bebmn



Patented Mar. 17, 1925.

UNITED STATES PATENT OFFICE.

ALBRECHT THIELE, F BERLIN, GERMANY, ASSIGNOR '10 CHEMISCHE FABRIK AUFAC- TIEN (VORM. E. SCHERING), OF BERLIN, GERMANY.

PHARMACEUTICAL PRODUCT.

No Drawing.

To all whom it may concern:

Be it known that I, ALBRECHT THIELE, citizen of Germany, residing atBerlin, Germany, have invented a new and useful Improvenient inPharmaceutical Products, of

which the following is a specification.

The invention relates to the preparation of a new pharmaceutical productwhich is formed by melting together 4-dimethylaminO-QB -dimethyI-Lphenl-fi-pyrazolon with .dipropylbarbituric acid The product is of yellowcolour, melts at about from 82 to 86 centigrade and is soluble in waterespecially when warmed, and in alcohol, ether and acetone. It is markedby valuable therapeutical pro, erties, particularly by excellentanalgesic e ects.

This product which must be supposed to be an addition-compound isprepared by melting together4-dimethylamino-23-dimethyl-l-phenyL5-pyrazolon with dipropylbarbituricacid in such a manner as to avoid decomposition, at a temperature notexceeding about 125 centigrade. Thus two molecules of4-dimethylamino-2.3-dimethyl-1- phenyl-5 pyrazolon and one molecule ofdipropylbarbituric acid are combined. It is desirable therefore to melttogether the two compounds in the above stated ratio, though one is notbound to it.

I Application filed May 18, 1923. Serial No. 639,974.

To perform the method of preparation one proceeds for instance asfollows:

Two molecules of 4-dimethylamino-23- dimethyl-l-phenyl-5-pyrazolon areheated with one molecule of dipropylbarbituric acid while the mixture isbeing well stirred, to a temperature of about 100 centigrade until thecompounds have been melted to a yellow liquid. The melted mass isfiltered off while hot and then is allowed to freeze.

claim as my invention:

1. As a new article of manufacture a product consisting of4-dimethylamino-23- dimethyl 1 phenyl 5 pyraz'olon anddipropylbarbiturie acid melted together.

2. As a new article of manufacture a roduct consisting of two moleculesof 4- dimethylamino 2.3-dimethyl-1-phenyl-5-pyrazolon and one moleculeof dipropylbarbituric acid, melting at about from 82 to 86 Centigradebeing soluble in water especially when warmed, in alcohol, ether andacetone, and possessing strong analgesic properties.

In testimony whereof I have hereunto set my signature in the presence oftwo subscribing witnesses.

DR. ALBRECHT THIELE. Witnesses E. HOLZERMAN,

Room T. Auonrvn.

